Question

我正在尝试了解如何在XP，Vista和Windows 7中获取从PEM格式导入的公钥（下面的代码中包含的示例）。示例代码将在XP和Windows Vista / 7上导入密钥，但不一样。

在Windows XP上，加密提供程序的名称中需要字符串“（Prototype）”，并允许调用CryptImportPublicKeyInfo来传递。

在Windows 7上，“（Prototype）”提供程序显然存在，但不支持对CryptImportPublicKeyInfo的调用，这会令人困惑。

这些操作系统之间的正确实现是什么样的？是否有必要检测XP并使用“（Prototype）”请求名称，而没有它用于其他操作系统？是否有可能在某些XP系统上仍会失败？

或者，有没有办法检测这种令人困惑的行为，并选择哪个加密提供商支持必要的呼叫？

Windows 7上的输出：

ANALYZING CRYPTOGRAPHIC SUPPORT FOR:
     "Microsoft Enhanced RSA and AES Cryptographic Provider"
     CryptAcquireContext success.
     CryptAcquireContext.1 success.
     CryptStringToBinary.2 success.
     CryptDecodeObjectEx success.
     CryptImportPublicKeyInfo success.
     SUCCESS.
ANALYZING CRYPTOGRAPHIC SUPPORT FOR:
     "Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)"
     CryptAcquireContext success.
     CryptAcquireContext.1 success.
     CryptStringToBinary.2 success.
     CryptDecodeObjectEx success.
     CryptImportPublicKeyInfo FAILED****.

Windows XP上的输出：

ANALYZING CRYPTOGRAPHIC SUPPORT FOR:
     "Microsoft Enhanced RSA and AES Cryptographic Provider"
     CryptAcquireContext success.
     CryptAcquireContext.1 success.
     CryptStringToBinary.2 success.
     CryptDecodeObjectEx success.
     CryptImportPublicKeyInfo FAILED****.
ANALYZING CRYPTOGRAPHIC SUPPORT FOR:
     "Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)"
     CryptAcquireContext success.
     CryptAcquireContext.1 success.
     CryptStringToBinary.2 success.
     CryptDecodeObjectEx success.
     CryptImportPublicKeyInfo success.
     SUCCESS.

产生该输出的C ++源代码:(需要crypt32.lib）

#include <stdio.h>
#include <tchar.h>
#include <windows.h>
#include <wincrypt.h>

bool windowsAcquireProviderContext(HCRYPTPROV *pHandleProv, LPCTSTR pProviderName);
bool analyzeCryptographicSupport(LPCTSTR pProviderName);

int _tmain(int argc, _TCHAR* argv[])
{
    analyzeCryptographicSupport(MS_ENH_RSA_AES_PROV);
    analyzeCryptographicSupport(L"Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)");
    return 0;
}

bool windowsAcquireProviderContext(HCRYPTPROV *pHandleProv, LPCTSTR pProviderName) {
    WCHAR *pContainerName = L"blah blah blah";
    if(!CryptAcquireContext(pHandleProv, pContainerName, pProviderName, PROV_RSA_AES, CRYPT_SILENT)) {
        if(GetLastError() == NTE_BAD_KEYSET) {
            if(CryptAcquireContext(pHandleProv, pContainerName, pProviderName, PROV_RSA_AES, CRYPT_NEWKEYSET|CRYPT_SILENT)) {
                return true;
            }
        } 
    }
    return true;
}

LPCWSTR pwszPemPublicKey = 
    L"-----BEGIN PUBLIC KEY-----\r\n"
    L"MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQC6GUVcbn92bahlwOskKi8XkG9q\r\n"
    L"Vq863+C4cOWC6HzJojc011pJFFIBu8/pG1EI8FZJdBmTrFaJTriYw1/SpbOH0QqE\r\n"
    L"eHanT8qWn+S5m9xgDJoWTBJKcnu3OHOvJJU3c8jOHQQnRWLfghJH4vnwStdiwUUY\r\n"
    L"SMWpwuHObsNelGBgEQIDAQAB\r\n"
    L"-----END PUBLIC KEY-----\r\n";
int pemPublicKeySize = wcslen(pwszPemPublicKey);

bool analyzeCryptographicSupport(LPCTSTR pProviderName) {

    printf("ANALYZING CRYPTOGRAPHIC SUPPORT FOR:\r\n");
    wprintf(L"\t \"%s\"\r\n", pProviderName);

    HCRYPTPROV hProv;
    if(!windowsAcquireProviderContext(&hProv, pProviderName)) {
        wprintf(L"\t CryptAcquireContext FAILED.\r\n");
        return false;
    }
    wprintf(L"\t CryptAcquireContext success.\r\n");

    DWORD blobSize;

    if(!CryptStringToBinary(pwszPemPublicKey, pemPublicKeySize, CRYPT_STRING_BASE64_ANY,  NULL, &blobSize, NULL, NULL)) {
        CryptReleaseContext(hProv, 0);
        wprintf(L"\t CryptStringToBinary.1 FAILED****.\r\n");
        return false;
    }
    wprintf(L"\t CryptAcquireContext.1 success.\r\n");

    BYTE *pBlob = (BYTE *)malloc(blobSize);

    if(!CryptStringToBinary(pwszPemPublicKey, pemPublicKeySize, CRYPT_STRING_BASE64_ANY,  pBlob, &blobSize, NULL, NULL)) {
        free(pBlob);
        CryptReleaseContext(hProv, 0);
        wprintf(L"\t CryptStringToBinary.2 FAILED****.\r\n");
        return false;
    }
    wprintf(L"\t CryptStringToBinary.2 success.\r\n");

    CERT_PUBLIC_KEY_INFO *publicKeyInfo;
    DWORD publicKeyInfoLen;
    HCRYPTKEY hPublicKey;

    if(!CryptDecodeObjectEx(X509_ASN_ENCODING|PKCS_7_ASN_ENCODING, X509_PUBLIC_KEY_INFO, pBlob, blobSize, CRYPT_DECODE_ALLOC_FLAG, NULL, &publicKeyInfo, &publicKeyInfoLen)) {
        free(pBlob);
        CryptReleaseContext(hProv, 0);
        wprintf(L"\t CryptDecodeObjectEx FAILED****.\r\n");
        return false;
    }
    wprintf(L"\t CryptDecodeObjectEx success.\r\n");

    if(!CryptImportPublicKeyInfo(hProv, X509_ASN_ENCODING|PKCS_7_ASN_ENCODING, publicKeyInfo, &hPublicKey)) {
        LocalFree(publicKeyInfo);
        free(pBlob);
        CryptReleaseContext(hProv, 0);
        wprintf(L"\t CryptImportPublicKeyInfo FAILED****.\r\n");
        return false;
    }
    wprintf(L"\t CryptImportPublicKeyInfo success.\r\n");

    CryptDestroyKey(hPublicKey);
    LocalFree(publicKeyInfo);
    free(pBlob);
    CryptReleaseContext(hProv, 0);

    wprintf(L"\t SUCCESS.\r\n");
    return true;
}

Answer 1

您描述的问题的原因非常简单： Microsoft从

重命名为AES加密提供程序

"Microsoft Enhanced RSA and AES Cryptographic Provider (Prototype)"
"Microsoft Enhanced RSA and AES Cryptographic Provider"。

在WinCrypt.h中定义了相应的常量，您可以使用MS_ENH_RSA_AES_PROV和MS_ENH_RSA_AES_PROV_XP。

如果您不想测试操作系统的版本，可以CryptAcquireContext使用NULL作为pszProvider（并继续使用PROV_RSA_AES作为dwProvType）。在您的代码中，您可以添加analyzeCryptographicSupport(NULL);。

您还可以检查注册表项的“名称”值

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography\Defaults\Provider Types\Type 024

查看默认PROV_RSA_AES提供商的名称。

Answer 2

我想我记得在某个地方看到微软对这个名字进行了抨击，它要求“（Prototype）”出现在XP上并且不存在于Vista及以上版本中。我认为你必须在运行时检测平台并使用适当的字符串。

Windows XP与Vista / 7上的MS Crypto API行为

2 个答案: